Adhesive joint dressing compositions containing an alkali thickenable polymer

ABSTRACT

Adhesive dressing compositions are disclosed which are useful in restoring and improving adhesive joint surfaces such as grout surfaces in ceramic tile installations by easy, efficient methods. Such compositions form stain resistant, water repellent, washable coverings which adhere to most adhesive surfaces and further have properties of preferential adherability to certain adhesive surfaces compared with adjacent adherend surfaces. The compositions comprise a polymer in the form of an emulsion, an alkali-thickenable polymer, an alkaline material and water with other components including pigments, plasticizers and solvents.

BACKGROUND OF THE INVENTION

The restoration and preservation of hard surfaces generally utilizes thetechnology of the cleansing art which includes soaps and detergents; thesolvent treating art; and coating or paint technology. In fact, toproperly renew as well as protect surfaces, treatments often includeapplication of various compositions which require tiem-consumingpreparations, sequential treatments, and careful handling andapplication of the compositions. This is particularly the case where thesurface to be treated is adjacent to another surface which does notrequire the treatment. Examples of such surfaces include tiling orpaneling where only the adhesive joint surfaces between the pieces orpanels require treatment. Such surfaces may be found in the household,as in furniture such as on table tops, flooring, and walls; and onoutdoor surfaces, such as on boats; and in the point of bricks or otherconstruction blocks.

The term adhesive, as used to describe the composition of such jointsurfaces, generally refers to a substance capable of holding materialstogether by surface attachment, such as cementitious materials andpolymeric resins including, for example, organic resins and siliconeresins. The materials held together by the adhesive are termedadherends. The adhesive joint is also referred to as a grout,particularly when describing the joints between tile and otherconstruction materials. Typical grouting compositions are described, forexample, in U.S. Pat. No. 2,934,932 issued to Wagner and U.S. Pat. No.3,706,696 issued to Bernett et al.

Examples of adherends which are attached to each other by an adhesivejoint include structural clay products including brick, soaps,Slaughterhouse tile, glazed and unglazed clay block and non-Portlandcement-containing structural products such as plastic, metal,fiberglass, glass plate, etc. Other adherends include glazed andunglazed wall tile, quarry tile, glazed and unglazed ceramic mosaics,and glazed floor brick. The adhesive joints may consist of, for example,Portland cement, mastic grout and epoxy materials.

The adhesive material used to form an adhesive joint generally is chosenfor its strength and for its ability to form a strong bond to thesurface of the adherend. The adhesive usually contains large quantitiesof filler materials which add bulk to the adhesive as well as improvingits workability in applying it to the surface and increasing itsstrength. While the inculsion of fillers has these and other advantages,it also causes the adhesive jont to form a rough surface with manycrevices, often rendering the joint surface porous to liquids and highlyvulnerable to picking up diret and discoloration.

A grouting composition commonly employed in the ceramic tile industry isthat of the Portland cement type. Such compositions suffer from severalundesirable properties For example, the cement-type grouts are generallyrough textured and porous thereby collecting dirt and other matter andallowing the transpiration of water. The grout surface is reactive andit readily discolors and stains thereby detracting from its originalaesthetic or decorative appearance. The grouts are not readily avaliablein decorative colors to match or contrast with the ceramic tile. Inaddition, they often act as an environment for microorganisms. A wellknown example of such grouts is that found in bathroom tileinstallations.

While treatment of such joint surfaces with cleaning agents or solventsoffers a temporary solution to the problem, because of the nature ofthese surfaces, they are quickly apt to become dirty and require oftenand repetitive treatments. Moreover, such cleaning agents offer no aidin preserving the compositons in the joints.

In the past , the renewal of grout joints entailed the removal of thegrouting material by mechanical means, such as scratching and scraping,followed by re-installation of a similar material. This is expensive andtime consuming and does not solve the basic problem of poor performance.The same problem will recur since the same type of grouting compositionwas re-installed.

On the other hand, coatings and paints which offer a protective coatingfor the joint surfaces require difficult and tedious applications toprevent the coating of the adjacent surfaces. Removal of such coatingmaterial from the adjacent surfaces often require delicate cleaningmethods with noxious chemicals. As a result, devices for applying suchcoatings to very limited surface areas have been developed. Thesedevices range from the very familiar caulking gun to more sophisticateddevices like "Tileliner" manufactured by White Line, Inc., of Atlanta,Georgia. "Tileliner" has a special applicator which comprises a smallvial filled with a liquid of the consistency of paint. A special rubbercap device with an applicator wheel is attached to the vial. The wheelis rolled along the joint, effectively covering the surface area of thejoint in contact with the wheel. This technique still does not overcomethe very tedious and timely application over large areas. Moreover, itis dependent upon the applicatior not clogging with the coatingcomposition.

Additionally, the use of the applicator is also very limited by the sizeand shape of the joint to be coated. If the joint is narrower than thewheel width, the wheel does not touch the joint and the application isunsatisfactory. If the joint is wider than the wheel, a number ofstrokes with the applicator are required, resulting in a joint with anuneven appearance. If the joints are not straight, application isdifficult. In all cases when the applicator comes to an intersection andcrosses over a previously-applied area, it causes a raised area since itis thicker in this area than on either side of the intersection.

The coating composition used in the "Tileliner" as well as other knowncompositions are deficient in one or more respects. Many of thesecompositions cannot be applied over surfaces which are dirty or oily. Inmany cases the surfaces must first be extensively cleaned. As the jointsurfaces are generally roughly textured and porous, many compositions donot obtain good bonds and adhesion with the substrate. Additionally,compositions have not heretofore existed which could provide an adhesivejoint with acceptable water resistance, mildew proofing, and stainresistance. Many such compositions readily discolor and do not improvethe aesthetic or decorative appearance of the adhesive joint. Theaesthetic appearance not only includes color but also the texture of thecoated surface.

For example, the composition used in the "Tileliner" when cured does notyield a glossy texture and does not resist stains such as permanentblue-black ink. Also, the coating will not adhere well to the substrateif the substrate is not meticulously clean and dry.

Another problem with such compositions is the difficulty in removingexcess coating composition from adjacent surfaces. Removal requires useof special solvents. Not only are some of these solvents dangerous andodorous, but also remove some of the coating from the desired substrate.

SUMMARY OF THE INVENTION

The present invention relates to compositions which may be used asdressings capable of selectively adhering to substrate surfaces.

Compositions have now been discovered which can be formulated to have aconsistency for easy application to adherable substrates and haveproperties for preserving and protecting the substrate as well asimproving the aesthetic appearance of the adherable substrates. Thecompositions of the present invention are particularly adaptable forapplication to surfaces which are adjacent to other surfaces to whichapplication of the dressing is not desired. Such a surface would be, forexample, an adhesive joint surface which is the interface between twobodies held together by an adhesive.

The compositions of th present invention have the particular advantageof being adherable to most adhesive joint surfaces while thecompositions are easily removed from the adjacent surfaces of manyadherends. This is due to the discovery of their selective adherability,or their ability to adhere and bond to certain materials and not toothers. This property provides easy cleanup and simplified applicationmethods of the composition. The workable consistency of the compositionmay be modified to allow it to be applied to surfaces by a variety oftechniques.

The adhesive substrates upon which the compositions of the presentivention have been found most successful are those having non-pouroussurfaces which are indented or recessed below the surface of theadherends and porous surfaces which may be recessed or even or flushwith the adherend surfaces.

The dressing composition of the present invention attaches to substratesurfaces by chemcial and/or by physical interaction. Chemcially reactivesurfaces are generally most vulnerable to dirt and other contaminants inthat they react with numerous every day materials leading to staining.However, the reactive properties of such surfaces are utilized in thepresent invention as the dressing compositions herein disclosed actuallychemically react with these surfaces to form strong chemcial adhesivebonds and also neutralize the reactive properties of the surface toother materials. With respect to more inert substrate surfaces, thedressing composition herein disclosed have the ability to form strongadherent bonds although no chemcial reaction is detectable.

Another advantage of the composition of the present invention is thatthey can be formulated to provide the substrate with a protectivecovering, which covering when cured is relatively smooth textured,non-porous, stain resistant, water repellant, washable, mildew proof andhas the ability of being applied in various decorative colors, as wellas white. Moreover, the cured dressing is capable of withstanding attackfrom most common chemcial agents for at least short periods of time. Itis also capable of having a second layer applied thereover.

It has additionally been discovered that the compositions of the presentinvention can be applied over wet or dry areas of newly-installed or oldsurfaces. The compositions generally may be applied over surfaces whichare dirty. However, in some cases, nominal cleaning of the surface maybe helpful where the dirt (eg. oil) is not well anchored to thesubstrate and will not be easily dispersed by water or where the dirt isa good pigment (eg. carbon black) which might discolor the dressingcomposition by mixing into it.

The compositions of the present invention have particular utility in thetile industry. Tiles of various materials are mounted and installed withadhesive materials forming joints or grouts between the edges ofadjacent tile members. The compositions of the present invention areparticularly suitable for application over many of the materials used astile grouts, eg., mastic grouts. The compositions, upon being cured,maintain sufficient strength and withstand cracking of the surface.

For example, the compositions of the present invention have the abilityto prevent the powdering and cracking of Portland cement grouts,particularly located on dry wall installations where the tile isinstalled in areas where it does not come into contact with water.

Another advantage of the present invention is its surprising ability tochemcially react with cementitious surfaces such as Portland cementgrouts and form an exceedingly strong bond therewith.

A further advantage of the compositions of the present invention istheir ability to quickly resist the pick-up of dust on their freshlyapplied, ucured, exposed surface even in dirty environments. In othermaterials not having this advantage, upon curing, the dirt remains onthe surface and damages the appearance.

Accordingly, the present invention has the following objects:

It is an object of the present invention to provide a stable, one-partcomposition having a pleasant odor, which is non-poisonous, and whichadheres to substrate surfaces and modifies and improves the aestheticproperties of the substrate surfaces, while retaining the approximatecontour of the substrate surfaces.

It is another object of the present invention to provide a stable,one-part composition which adheres to substrate surfaces and which iscapable of forming a protective layer over such surfaces which is stainresistant, washable, resistant to most chemical agents and non-porous towater.

It is still another object of the present invention to provide adressing composition which is easy to remove from the substrate in itsuncured state but which becomes resistant to removal when cured.

It is a further object of the present invention to provide a dressingcomposition which adheres to and forms strong bonds to some substratesurfaces and not to other surfaces.

It is a still further object of the present invention to provide acomposition specially adaptable as a dressing for adhesive joint orgrout surfaces, which composition when covering the joinnt or groutimproves or modifies the aesthetic properties of the joint or groutsurface and provides such surface with a covering which is stainresistant, washable, resistant to most chemical agents and non-porous towater.

It is an additional object of the present invention to provide adressing composition which is protected by a microbicide.

It is another object of the present invention to provide a dressingcomposition which is easily applied by various techniques to both porousand non-porous substrates of varied dimensions which substrates may haveflat or contoured surfaces and be either level, higher or recessed withrespect to adjacent surfaces.

It is still another object of the present invention to provide adressing composition which may be used in multiple coatings.

It is a further object of the present invention to provide an efficientand economical method for restoring and protecting substrate surfacessuch as adhesive joints whether said joint surfaces are straight orcurved or of uniform or non-uniform shape or width and further whetherthe adhesive joint has a varying depth below the surface of theadherend.

It is still another object of the present invention to provide a methodof obtaining a smooth surface at the intersection of joint surfaces.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

According to the present invention, there are provided dressingcompositions capable of forming over substrate surfaces a non-porous,stain resistant, washable covering when cured, said compositioncomprising (i) a polymer in the form of an emulsion, said polymer may beselected from polymers of carboxylic acids, polymers of esters ofcarboxylic acids, and copolymers of a carboxylic acid or ester of acarboxylic acid with one or more monomers from the group comprisingcarboxylic acids, esters of carboxylic acids, acrylonitriles,acrylamides, aryls, alkenes and derivatives thereof, said polymercharacterized as being room-temperature curable and forming awater-resistant film when cured; (ii) an alkali thickenable polymercapable of substantially increasing its viscosity as its pH is increasedabove neutral pH, said polymer may be selected from the group consistingof polymers of carboxylic acids, polymers of esters of carboxylic acids,and copolymers of a carboxylic acid or ester of a carboxylic acid withone or more monomers from the group comprising carboxylic acids, estersof carboxylic acids, acrylonitriles, acrylamides, aryls, alkenes andderivatives thereof, said polymer characterized as beingroom-temperature curable and forming a water-resistant film when cured;(iii) an alkaline agent present in sufficient amounts to thicken thealkalithickenable polymer; and (iv) water; wherein the dispersion of atleast one of said polymer components becomes destabilized in thepresence of polyvalent cations and wherein the total weight of polymersolids is in the range of 5-60% by weight of the total composition andwherein the composition has a thixotropic rheology and a viscosity whichis greater than about 50,000 cps at 70° F.

Another feature of the present invention is to include in the dressingcomposition described immediately above a solvent which has the abilityto reduce the time rate of film formation of the composition.

A further preferred feature of the present invention is to include inthe dressing composition comprising components (i), (ii), (iii), and(iv) above, a pigment ingredient which is present in sufficient amountsto render the cured dressing with adequate opacity and desirable colorto obscure the substrate on which it is applied.

A still further preferred embodiment of the present invention aredressing compositions comprising the components (i), (ii), (iii), and(iv) as described above further comprising a plasticizer.

Another preferred embodiment of the present invention are dressingcompositions comprising the components (i), (ii), (iii), and (iv) asdescribed above, further comprising a microbicide or mildewcide forinhibiting the growth of microbes such as bacteria and fungi both in thecomposition when stored and in the cured dressing.

A still further embodiment of the present invention is to provide amethod for restoring, protecting and improving surfaces such as adhesivejoints, said method comprising the steps of (i) applying the dressingcompositions as described hereinabove; and (ii) removing excesscomposition from the surfaces adjacent to the treated surfaces.

An additional embodiment of the present invention is the method ofconverting or rendering the face surfaces of a tile-grout installationinto one continuous water repellent, stain resistant surface.

Yet another embodiment of the present invention is a tile assemblycomprising a plurality of tiles arranged in an edge-to-edge,spaced-apart relationship wherein said spaces form joints containing acured grouting composition on which there is a layer of a dressingcomposition as hereinabove described.

The first ingredient in the composition is a polymer in the form of anemulsion which is stable in the alkaline environment of the compositionitself, and is further stable in the sense of not degrading ordepolymerizing when applied to such substrates as Portlandcement-containing materials. Additionally, such polymers should becolor-stable, that is able to withstand decolorizing or yellowing uponcontinued exposure to the alkaline environment, the generally to theconditions to which the dressing composition is applied. Such polymerscure at room temperature and form a water-resistant film. Moreover, suchpolymers should be easily combined with the other ingredients which maybe included in the composition including the pigments.

One of the distinguishing properties of the polymer emulsion is that theemulsion system becomes unstable in the presence of polyvalent cations.This instability is not due to a degrading or depolymerization of thepolymer itself, but rather to a breakdown in the emulsion phase whereinthe microscopic droplets of the polymer no longer remain suspended inthe liquid phase.

The emulsion state is a quasi stationary state in which the dispersionof an insoluble or slightly soluble liquid or solid polymer material isdispersed in a medium to low viscosity liquid phase. The polymer remainssuspended or dispersed in the liquid phase either because parts of thepolymer are soluble in the liquid phase, or an emulsifier additive ispresent, or by both means. Such an emuslifier forms a loose bridge orlink between portions of the polymer molecule and the liquid dispersingmedium aiding in stabilizing the dispersion of the polymer in the liquidphase.

A characteristic property of polymer emulsions useful in the presentinvention is that the stability of the emulsion is affected by thepresence of polyvalent cations. Classic examples of polymers which formsuch emulsions are those having carboxylic acid pendant groups and/orare anionically dispersed.

An example of a polymer emulsion having this destabilizing propertywhere the polymer constituent is anionically dispersed is Neoprene LatexLD2931-42 manufactured by DuPont & Nemours.

Examples of polymers in the form of an emulsion suitable in thecomposition of the present invention include those polymers derived frompolymerizable carboxylic acids, esters of such carboxylic acids andcopolymers of such carboxylic acids or esters of carboxylic acids withone or more monomers from aryl, alkene, acrylonitrile, acrylamide, othercarboxylic acids and esters of carboxylic acids, and derivativesthereof. A preferred group of polymerizable carboxylic acids includesubstituted and unsubstituted alpha-olefinic monocarboxylic acids suchas acrylic acid and methacrylic acid and their homologues. A preferredgroup of esters of said alpha-olefinic monocarboxylic acids wouldinclude the esters of said carboxylic acids with saturated aliphaticmonohydric alcohols, eg. an alkyl acrylate. Specific examples of suchmaterials are the acrylic emulsion polymers produced by the Rohm andHaas Company. These acrylic emulsion polymers are available under thetradenames "Rhoplex AC-61, Rhoplex LC-40, Rhoplex AC-707".

An examination of the instability of Rhophex AC-61 emulsion in thepresence of calcium ions will be illustrative of the propertiesdesirable in the polymer emulsion component. The addition of smallamounts of calcium chloride solution (1.0 N) to the Rhoplex AC-61aqueous emulsion causes the emulsion to break up as the polymercomponent apparently agglomerates forming cottage cheese-type curdswhich result in the polymer separating from the liquid phase.

Another essential component in the composition of the present inventionis the alkali thickenable polymer. As this terminology suggests, thisgroup of polymers is characterized as causing the composition to thickenyielding a substantial increase in viscosity as its pH is increasedabove about 8.5. This group of polymers is generally provided in theform of an aqueous sol, colloidal dispersion or emulsion of polymerparticles, only partly in solution at near neutral pH. Although stilldispersions, in some cases these polymers may be referred to as watersoluble as they appear as "solutions" because the particle size of thepolymer particles is below that visible to the eye. An acid monomercontent of form 6 to 25% by weight of the polymer is usually adequate tosufficiently solubilize the polymer, but this may depend on thedistribution of the acid groups in the polymer chain. A good discussionof the solubility of polymers is found in "The Chemistry of Organic FilmFormers" by D. H. Solomon published by J. Wiley & Sons (1967) which isincorporated herein by reference.

The alkali thickenable polymers, like the emulsion polymers, must becompatible with the other components in the composition. For example,the polymers must not degrade or depolymerize in the presence of theother components, nor in the presence of such materials to which it maycontact when used in the dressing compositions as herein described.Moreover, these polymers should be color stable and not yellow uponcontinued exposure to an alkaline environment.

However, a property distinguishing the alkali-thickenable polymer fromthe emulsion polymer is its ability to significantly increase theviscosity of the composition as its pH is increased above a certainpoint in the alkaline range. the actual means by which the polymerthickens at increased pH is not important although it has been notedthat some polymers achieve this thickening because the alkalinity causesthe polymer to swell and uncoil in its dispersing medium. The degree ofthickening a polymer achieves at alkalinity depends upon the molecularweight of the polymer and the composition of the polymer including thenumber, distribution and nature of its pendant substituent groups.

The alkali-thickenable polymer may be similar to emulsion polymercomponent in that the stability of the emulsion or dispersion it formsmay be affected by the presence of polyvalent cations. Generally, thisproperty is not usually identified by the manufacturer of the polymer,as instability of a polymer in the form of a dispersion is considered,in most applications, an undersirable feature. Therefore, the emulsionor dispersion of the alkali thickenable polymer must be tested todetermine its instability to polyvalent ions. The actual cause of thisinstability is not important. It may be due to, for example, thepresence of acid pendant groups or the manner by which the polymer isdispersed.

One such test which has been formulated to determine the usefulness ofcertain alkali thickenable polymers includes the addition of calciumchloride solution to the subject polymer dispersion or emulsion todetermine if the polymer dispersion is unstable. This is a similar testto that used to determine useful polymer emulsion ingredients. Such atest may be carried out by diluting 1.0 ml of a thickenable polymer suchas Acrysol WS-50 with 100 ml of water. The optical density of such asolution is recorded. Then 1.0 N calcium chloride solution is added at asteady rate of 0.5 ml/min. The point of maximum change of opticaldensity is determined. This change in optical density is caused by theprecipitation of the polymer from the dispersing medium. This test isrepeated to confirm the quantitative nature of the titration.

Some polymers not desirable in the present invention do exhibitprecipitation in the presence of high levels of calcium ions. However,this precipitation does not yield a quantitative, reproducible,titration point because the precipitation is attributable to aphenomenon known as "salting-out".

The alkali thickenable polymer also resembles the emulsion polymercomponent in its general chemical make-up. It may also be derived frompolymerizable carboxylic acids, esters of carboxylic acids, andcopolymers of such carboxylic acids or esters of such carboxylic acidswith one or more monomers from aryl, alkene, acrylonitrile, acrylamide,other carboxylic acids and esters of carboxylic acids or derivativesthereof. Preferred polymerizable carboxylic acids include substitutedand unsubstituted alpha olefinic monocarboxylic acids.

Examples of useful alkali thickenable polymers include the Acrysolaqueous colloidal acrylics manufactured by the Rohm and Haas Comparnyunder such tradenames as WS-50, WS-32, WS-24 and ASE-60. Other polymerssuitable as the alkali thickenable polymer include Carboset manufacturedby the B. F. Goodrich Company.

Generally, the total weight of polymer solids in the uncured compositionis in the range of 5-60% and preferably 10-40%. Of this polymer solidcontent, it is preferable to have at least 5% of the polymer solids bethe emulsion polymers. The minimum amount of thickenable polymerspresent will depend upon the specific polymer used and the desiredviscosity of the uncured composition. The uncured dressing preferablycontains at least about 20% by weight volatile components.

Where resistance to water is desired in the final cured dressingcomposition, the water sensitivity of the alkali thickenable polymermust be considered.

Successful dressing compositions in accordance with the presentinvention have also been formulated wherein the dispersion of only oneof the polymer components present in the composition, namely, either theemulsion polymer or the alkali thickenable polymer, is destablized bypolyvalent cations. Moreover, the present invention contemplates the useof mixtures of polymer components, only some being destabilized.

an alkaline agent or base is utilized to increase the pH of thecomposition. Monobasic water-soluble alkaline agents are preferred. Insome instances, it has been observed that polybasic molecules tend toreact with some thickeners and produce a solid gel which synerizes.Also, polybasic agents contain polyvalent cations, which is present inthe composition, could prematurely destabilize the emulsion polymer orthickener. While small amounts of polybasic compounds may be present, itis preferable to have at least one monobasic compound present as acontributing alkaline agent. Examples of such monobasic compoundsinclude ammonium and alkali metal hydroxides and simple aliphaticamines. Properties which should be considered in choosing the alkalineagents include minimal odor, and properties which do not significantlyeffect the water sensitivty of the cured film (if such properties aredesired) and do not interfere with the film formation. It is alsodesirable to use an alkaline agent which is volatile as long as it doesnot cause an unfavorable odor.

Certain of the water-soluble solvents can prevent the formation of thefilm prematurely. Useful water-soluble solvents have a vapor pressure atroom temperature lower than that of water and therefore tend to reducethe rate of evaporation of liquid constituents of the composition. Thesesolvents can also affect the viscosity and rheology of the composition.The water-soluble solvent is chosen so as not to detrimentally affectthe other ingredients in the dressing composition nor affect thephysical stability of the dressing composition.

Among the solvents found most useful in the present invention are theshort-chain diols such as ethylene glycol and propylene glycol. Theseingredients are also referred to as anti-drying aids. Not only do thesesolvents affect the film formation, but they also can function aspigment dispersers. Generally, ethylene glycol is the preferred diolalthough other diols may be used. Each of these solvents have differingproperties and the amounts of each to be used in the composition must bedetermined on the basis of the properties desired.

The compositions of the present invention require relatively highquantities of volatile components and small amounts of non-volatilecomponents, other than the polymer binders. As the dressing compositioncures, the volatile components from the composition evaporate. Thecomposition, therefore, shrinks in volume, leaving a layer of dressingover the substrate sufficiently thin to cause the new dressing surfaceto approximate the contour of the substrate surface.

The cured dressing comprises the non-volatile components of thecomposition which are predominantly the polymer binders and the pigmentwhen included in the compositions. To obtain the glossy finish of thecured dressing as well as the other advantages, a high binder to pigmentradio is desired. Preferred pigment to binder weight ratios are at least1:1.

There is little criticality in the choice of the pigment other than itsstability at alkaline pH's and that it not react with the othercomponents in the polymer dispersion system and should not causeprecipitation or coagulation of the other ingredients.

Generally, those materials known in the adhesive and paint art as"pigments" are useful in the present composition. These pigments are inthe form of small particles of up to about 15 microns in diameter.Examples of such pigments are titanium dioxide, light chromium green,yellow iron oxide, ASP-172, ASP-602, ASP-400P, Attagel 150, fromEngelhard Industries, and 15 micron silica. Also contemplated withinthis class of pigments are those materials known as extenders. Extendersgenerally have a particle size larger than pigments, but they aresufficiently small to give the cured dressing composition sufficientopacity to render it aesthetically useful when applied to substrates.

The quantity and nature of the pigments affects the viscosity andworkability of the uncured dressing composition. By the nature of thepigment is meant the density, surface area and wet out volume of thepigment. For a given amount of a pigment, a certain minimum quantity ofpolymer components referred to as the binder solids is necessary toassure satisfactory workability of the composition.

A helpful guide for determining the relationship of the pigment to otheringredients in the composition is the oil absorption value of thepigments as determined by ASTM D-281-31 spatula rub-out method.

The pigment in addition to coloring the composition may affect thetemperature stability of the viscosity of the uncured composition.Generally, as the temperature increases, the viscosity of thecomposition decreases at a rapid rate. The presence of some pigmentstend to increase this temperature dependence. Therefore, the propertiesof the composition may become very dependent upon the temperature wherea pigment such as titantium dioxide is present alone as the pigmentingredient. It has been found that where such dependence is too extreme,the addition of a second pigment component such as attapulgite clay mayreduce this temperature dependence while maintaining the desirableopacity.

As noted above, the compositions of the present invention also act as aphysical preservative for the substrate surface by encapsulating andholding together the often loose granular substrate surfaces. Theproperties for accomplishing this purpose are enhanced by the presenceof coalescing aids and plasticizers. Generally, the formation of thefilm is aided by the presence of solvents which soften the polymercomponent and allow them to coalesce at a lower temperature, or allowthem to form a film more rapidly at a given temperature. These solventsor coalescing aids are sufficiently volatile, that after film formation,they leave the film by evaporation allowing the film to return to itsoriginal hardness. Where substances with low volatility are used, theyremain in the film causing the film to remain soft. These lattersubstances which remain in the film are called plasticizers. Examples ofcoalescing aids include diacetone alcohol and Butyl Cellosolve,manufactured by Shell Chemical. Paraplex WP-1, manufactured by Rohm andHaas, is an example of a plasticizer.

It is often beneficial to include an ingredient to inhibit the growth ofmicrobes such as bacteria and fungi materials both in the preparedcomposition and in the cured coating. Microbicides, includingbcteriocides and mildewcides, are particuarly usable in the compositionof the present invention. Useful materials include, for example,Nopcocide, manufactured by the Nopco Chemical Division of DiamondShamrock Chemical Compnay, and Vancide, manufactured by Vanderbilt & Co.

Other polymers which do not form unstable emulsions in the presence ofpolyvalent cations may be included in the composition for purposesincluding improving the strength, water resistance, stain resistance,etc., of the cured composition.

The dressing composition of the present invention can be applied tovarious substrate surfaces by numerous conventional methods ofapplication. As discussed above, the dressing composition can be appliednot only to flat surfaces but also to curved or contoured surfaces ofvarying sizes and shapes which are elevated, flush or recessed withrespect to adjacent surfaces.

As indicated above, the dressing composition bonds better to chemicallyreactive surfaces, such as surfaces containing cememtitious materials,than to non-reactive surfaces due to the presence of chemical bonding inaddition to physical bonding. Therefore, joint surfaces containing suchreactive materials, whether they be flat or contoured, or recessed orflush with the adherend surface, are excellent substrates for use withthe dressing compositions.

The dressing composition also bonds well to less reactive ornon-reactive substrate surfaces which are porous in that it forms goodphysical bonds with such surfaces. Such porous substrate surfaces may beflat or contoured or recessed or flush with the adherend surface andobtain excellent results.

Non-porous, non-reactive surfaces have also been found to act as goodsubstrates for the dressing compositions where the surface is notperfectly flat and even or flush with the adherend surface. The dressingcomposition also bonds well to such non-porous, non-reactive surfacesand the other properties of the composition including its thixotropicrheology give it many advantages for easy and efficient application.

A preferred application of the composition of the present invention isits application over joint surfaces and adjacent surfaces which utilizethe selective adherability properties of the compositions. As indicatedabove, selective adherability is generally the ability of thecomposition to form better bonds with certain surfaces than with othersurfaces. For example, the dressing compositions form better bonds tochemically reactive surfaces, particularly those containing polyvalentcations, than to non-reactive surfaces. Therefore, where the jointsubstrate surface contains a reactive constituent such as a cememtitiousmaterial, the dressing composition will react chemically and form abetter bond than to an adjacent adherend surface of a less reactive ornon-reactive surface.

A similar example of where selective adherability of the dressingcomposition may be utilized is where the joint adhesive surface is moreporous than the surface of the adjacent adherend. Again, the dressingcomposition will form a beter bond with the joint surface than theadherend surface allowing for easy clean-up of the composition from theadherend surface without wiping off the composition from the joints.

Typicaly, where an adherend-adhesive configuration is used, such as inthe construction industry, a porous and/or reactive adhesive joint isadjacent to a non-porous, non-reactive adherend. Adherends such as tilesand other pieces used in floorings and wall coverings are highly glossedand non-reactive for long-lasting as well as aesthetic purposes. Incomparison, the adhesive joint is typically more reactive and moreporous. Examples of such adherend-adhesive configurations which utilizethe selective adherability properties of the dressing compositionsinclude: ceramic tile with Portland cement or mastic grout joints;glazed construction blocks with dry-set mortar joints; quarry tile withdry-set mortar joints.

As discussed above, the dressing composition of the present inventionaccomplishes more than the mere improvement of the aesthetic propertiesof adherend-joint configurations. The fact that the dressingcompositions can render surfaces impenetrable to wear provides numerousother advantages and uses. For example, the dressing composition canconvert a ceramic tile wall with porous cement joints into acontinuously impervious surface. Essentially, the ceramic tile wall isconverted into an installation which meets the building codes requiringthis type of surface in wet areas.

Additionally, the smooth joint and tile surface make a surface to whichdirt and germs have difficulty clinging and can be easily removed withroutine cleaning. This is in contrast to the porous cement joints whichare known to harbor germs and mildew, as well as dirt. Cleaning causesadditional dirt and water to be absorbed from the cleaning agent intothe joints making them dirtier. The application of the dressingcomposition improves the sanitary and durable nature of theinstallation.

The rheology and other physical properties of the dressing compositionof the present invention allow it to be applied to substrates by anumber of methods. The viscosity of the dressing composition is greaterthan 50,000 cps and less than 10,000,000 cps at 70° F and shows lessthan a factor of 100 change in viscosity at 120° F, never falling below50,000 cps.

It has been found that the apparent viscosity of the composition ischanged by the shear forces or pressure to which the composition issubjected during the manipulation for applying to the substrate surface.This rheology is evidenced as a change in the apparent Brookfiedviscosity with spindle speed. A practical illustration of this rheologyis that the amount of material delivered from a caulking tube in a givenperiod of time varies when the applied pressure is changed.

The dressing composition with thixotropic rheologies are found to bemost useful. Compositions with this rheology are manipulated easilyunder pressure, but remain in place once the pressure is removed.Generally, the compositions of this invention show apparent Brookfiedviscosity ratios around 3 or 4when the 0.5 rpm value is compared withthe 100 rpm value at 70° F. The actual value is not critical, butgenerally compositions with ratios approaching 1 or less would not beable to be applied easily since they may tend to wash out of the jointswhen the excess dressing is wiped or washed from the adherend surface.

One method for applying the grout dressing is by a "smear and wipe"technique. Bu this method, the dressing is applied with a damp sponge,with a cloth or by hand to the joint surfaces with portions of thedressing incidentally being applied also to the adjacent adherend. Nospecial care is taken to shield or protect the adherend surfaces fromthe dressing. The dressing will not injure the surface of the adherendand the dressing is easily removed from its surface.

Other methods of application include, for example, trowelling; brushing,as with a paint brush; with a damp sponge or cloth material, or thehand; rolling, as with a paint roller; or extrusion, as with atoothpaste-type tube or caulk gun. The consistency of the compositionenables it to be applied successfully by any of these techniques andothers. Naturally, the choice of the particular technique will dependupon the size and shape of the area to be covered. Application methodsmay cover the adherend as well as leave a thick layer of uncureddressing over the joint. However, when washed, the excess dressing isremoved from the adherend and excess dressing is removed from the joint,leaving a thin layer adhering to the joint surface.

The following examples are given to merely illustrate some of thepreferred embodiments of the present invention.

EXAMPLE 1 Comparison of Alkaline Agents

As discussed above, it has been found that monobasic alkaline materialsare superior to polybasic materials. The effect of different alkalinematerials on the viscosity and thickening properties is illustrated by acomparison of the five compositions described in the table below ascompositions A through E. These compositions are comparable in theirchemical make-up except for the alkaline ingredient present in each.Compositions D and E, both containing mono-basic alkaline materials, hadgood, stable viscosities, and effectively thickened and formed a filmwhen set on the substrate. Composition B did not thicken sufficiently tobe applied to joint surfaces without running out. It is noted that thehexamethylene tetramine in composition B is not an alkaline agent, i.e.,it does not form an alkaline solution with water. Composition C was tooslow in thickening and did not obtain a desirable viscosity but ratherformed a gel-like structure. This gel-like structure then formed arubber-like mass by a phenomenon known as syneresis wherein the materialcontracts, squeezing out the liquid medium. Composition A thickened morerapidly than composition C and formed an even stiffer gel which becamerubber-like upon syneresis without obtaining a desirable viscosity forapplication of the composition to the substrate.

    ______________________________________                                        Component       A      B      C    D    E                                     ______________________________________                                        AC-61           35.37  35.37  35.37                                                                              35.37                                                                              35.37                                 WS-50           38.35  38.35  38.35                                                                              38.35                                                                              38.35                                 Ethylene Glycol 12.55  12.55  12.55                                                                              12.55                                                                              12.55                                 Titanium Dioxide                                                                               9.37   9.37   9.37                                                                               9.02                                                                               9.43                                 Mildewcide       0.19   0.19   0.19                                                                               0.14                                                                               0.14                                 Plasticizer      1.91   1.91   1.91                                                                               1.92                                                                               1.92                                 Water            1.29   1.29   1.29                                                                              --   --                                    Diethylene Triamine                                                                            1.01  --     --   --   --                                    Hexamethylene Tetramine                                                                       --      1.04  --   --   --                                    Triethylene Pentamine                                                                         --     --      1.12                                                                              --   --                                    Ammonium Hydroxide(conc)                                                                      --     --     --    1.81                                                                              --                                    Sodium Hydroxide (33%)                                                                        --     --     --   --    1.80                                 ______________________________________                                    

EXAMPLE 2

The data reported in the Table below shows the effect of the pigment andthe extender ingredients on the viscosity of the dressing composition asa function of temperature.

The visosity is an important factor with respect to the method ofapplying the composition to the substrate. Moreover, substrates whichhave flat surfaces, i.e., not contoured, may not readily hold or receivecoating compositions of low viscosities.

The addition of pigment (without the extender) to the mixture of filmformers sharply increases the temperature dependence of the composition.This is illustrated by comparing compositions A with C and compositionsE with F. The compositions A and E both contain the pigment and haveviscosities varying more sharply with temperature than the comparablecompositions C and F without the pigment. When extender is substitutedfor all or part of the pigment, as in compositions B and D, theviscosity of the compositions becomes less sensitive to temperature.

    __________________________________________________________________________    Component A    B    C    D    E    F                                          __________________________________________________________________________    Acrylic Emulsion                                                                        35.55                                                                              35.55                                                                              35.55                                                                              21.84                                                                              21.84                                                                              21.84                                      Thickener 38.55                                                                              38.55                                                                              38.55                                                                              47.80                                                                              47.80                                                                              47.80                                      Anti-drying aid                                                                         12.62                                                                              12.62                                                                              12.62                                                                              10.83                                                                              10.83                                                                              10.83                                      Pigment   9.42 --   --   8.31 15.66                                                                              --                                         Extender  --   9.42 --   7.35 --   --                                         Mildewcide                                                                              0.14 0.14 0.14 0.12 0.12 0.14                                       Alkaline Agent                                                                          1.81 1.81 1.81 1.82 1.82 1.82                                       Plasticizer                                                                             1.92 1.92 1.92 1.94 1.94 1.94                                                 Viscosity (cps)                                                     __________________________________________________________________________    Temp.                                                                             A     B     C     D     E     F                                           __________________________________________________________________________     65°                                                                       530,000                                                                             780,000                                                                             900,000                                                                             2,760,000                                                                           2,300,000                                                                           2,340,000                                    70°                                                                       360,000                                                                             660,000                                                                             640,000                                                                             2,080,000                                                                           1,780,000                                                                           1,780,000                                    85°                                                                       180,000                                                                             370,000                                                                             280,000                                                                             1,220,000                                                                           860,000                                                                             900,000                                     105°                                                                        50,000                                                                             180,000                                                                             170,000                                                                             540,000                                                                             340,000                                                                             580,000                                     120°                                                                        20,000                                                                             110,000                                                                             100,000                                                                             390,000                                                                             220,000                                                                             420,000                                     __________________________________________________________________________

EXAMPLE 3

The following composition was prepared as a batch on a Cowles Dissolver:

    ______________________________________                                                         Wt in Grams                                                  ______________________________________                                        Acrysol WS-50      2,000.00                                                   Nopcocide N-96     80.00                                                      TiO.sub.2 - RANC   80.00                                                      Ethylene Glycol    120.00                                                     Diacetone Alcohol  140.00                                                     Butyl Cellosolve   140.00                                                     Defoamer           0.50                                                       NH.sub.4 OH to pH of 9.0                                                                         42.00                                                      AC-61              2,000.00                                                   Hegman Grind Approximately 20 - 30 μ                                       ______________________________________                                    

This composition was used to dress cement grout joints which werediscolored on a wall of glazed white wall tile. The composition wastrowelled on the joints. The drying rate was slow enough to allow easytrowelling, but thin layers of the dressing which were allowed to drywere difficult to remove.

The appearance of the joints were improved. The white wall looked "new".When the composition dried, the application of permanent blue-black inkto the surface did not stain the dressing. The ink was wiped away with adamp cloth. Application of ink to untreated cement joints caused theformation of a spot which could not be removed by any cleansing methodshort of bleaching.

The above composition was tinted yellow with a yellow pigmentdispersion. The pigment was just mixed in. The composition was appliedto a wall of yellow tile with dirty joints. The effect was dramatic. Theappearance of the whole wall was improved. Similar compositions wereprepared having blue pigment and a brown (iron oxide) pigment. In eachcase the joints on which the dressings were applied yielded dramaticimprovement in the aesthetic properties of the wall.

The compositions were also applied to a floor of ceramic mosaics withsimilar results obtained.

EXAMPLE 4 Preparation of a Pigmented Tile Grout Dressing

Pre-dispersed pigments may be incorporated in the dressing compositionsto obtain the desired color. The following clear tile grout dressingcomposition was prepared by mixing the ingredients on the CowlesDissolver.

    ______________________________________                                        WS-50            794.0                                                        AC-61            892.0                                                        Mildewcide       3.4                                                          Plasticizer      53.2                                                         Ethylene Glycol  147.9                                                        NH.sub.4 OH      35.4                                                                          1,925.9 grams                                                ______________________________________                                    

It was noted that the Mildewcide ingredient was the most difficultcomponent to disperse in the composition.

The composition obtained was clear to cloudy in appearance. Thiscomposition was applied by trowelling as a thin film onto the joints ona quarry tile panel. The panel had been grouted with a TECAdhesives-Portland cement joint filler of brown color. The dressingcomposition yielded a glossy, clear layer over the joints which sealedthe joint surface to water.

A. The clear tile grout dressing as described above was colored bymixing into it a small amount of Dutch Boy latex tinter of the burntumber color. The resulting composition had a very even, uniform and deepcolor, and retained this color after being applied to Portland cementjoints which initially had a dirty gray color.

B. An additive composition was prepared on a planetary mixer to which apre-dispersed pigment mixture could be added. This additive compositioncomprised the clear tile grout dressing described above but excludingthe mildewcide and ethylene glycol ingredients of the dressing. Themildewcide and ethylene glycol were instead mixed on a Cowles dissolverdirectly with the following pigment mixture:

    ______________________________________                                        Source        Pigment                                                         ______________________________________                                        American Cyanamid                                                                           Valencia Orange   65 g                                          American Cyanamid                                                                           Cyan Green        10 g                                          Pfizer        Pure Yellow Iron Oxide                                                                          10 g                                          GAF           Permanent Yellow  65 g                                                        Suprapaste                                                      ______________________________________                                    

This pigment mixture was then combined with the additive compositionyielding a uniformly colored tile grout dressing which effectivelyachieved and maintained its satisfactory coloring when applied to adirty gray cement-based tile grout.

EXAMPLE 5 Effect of Coalescing Aids or Plasticizers on a Tile JointDressing

A. A highly colored tile joint dressing, i.e., of high pigment content,was prepared on the Cowles dissolver containing the followingingredients:

    ______________________________________                                                      Grams     Wt %                                                  ______________________________________                                        WS-50           2,000.0     42.4944                                           Mildewcide      8.0         0.1899                                            Light Chromium Green                                                                          200.0       4.259                                             Ethylene Glycol 400.0       8.550                                             AC-61           2,000.0     42.4944                                           Antifoam        4.5         0.0960                                            NH.sub.4 OH     94.0        1.9972                                                            4,708.5     99.9997                                           ______________________________________                                    

This tile grout dressing had a deep chromium green color. It was appliedby trowelling to cement joints on a section of wall tile. Upon drying,some cracking was evident on the cement joints coated with thisdressing.

B. Diacetone alcohol was added to the dressing composition described inA above in an amount of 3% by weight of the above dressing. Thiscomposition was then applied to another section of cement joints on thewall tile. Upon drying, no cracks were observed in the areas coveredwith the tile grout dressing.

C. To the tile grout dressing composition described in A above was added3% by weight of Paraplex WP-1. This tile grout dressing was then appliedto another section of cement joints on the wall tile. Upon drying, nocracking occurred on the cement joints coated with the tile groutdressing.

When substantial quantities of pigment or other filler is contained inthe tile grout dressing of the present invention, it is advantageous toinclude in the composition a coalescing agent or plasticizer to inhibitthe cracking of the coating upon curing over the joint substratesurface.

EXAMPLE 6

This example concerns the effect of various watersoluble solvents on theviscosity and rheology properties of compositions of the presentinvention. Three compositions were prepared having the ingredients asdescribed in the table below. Composition A contained ethylene glycol asthe solvent; Composition C contained propylene glycol as the solvent;and composition B contained a mixture of both propylene glycol andethylene glycol. From the viscosities of these compositions as reportedin the table, it is clear that the different solvents render differentviscosities to the composition.

    ______________________________________                                        Component     A         B         C                                           ______________________________________                                        Rhoplex AC-61 35.55     35.55     35.55                                       Acrysol WS-50 38.55     38.55     38.55                                       Titanium Dioxide                                                                            9.42      9.42      9.42                                        Plasticizer   1.92      1.92      1.92                                        Ethylene Glycol                                                                             12.62     6.31      --                                          Propylene Glycol                                                                            --        6.31      12.62                                       Ammonium hydroxide                                                                          1.81      1.81      1.81                                        ______________________________________                                        Temperature Viscosity (cps)                                                   ______________________________________                                        65°  580,000    256,000    184,000                                     70°  360,000    200,000    160,000                                     85°  180,000    179,000     72,000                                     105°  50,000     24,000     16,000                                     120°  20,000     8,000      8,000                                      ______________________________________                                    

EXAMPLE 7

This example concerns the effect of excluding from the composition ofthe present invention the polymer ingredient which is in the form of anemulsion. Two compositions were prepared and are described in the tablebelow. Composition A did not contain any emulsion polymer. Composition Bdid not include any emulsion polymer but contained a differentwater-soluble solvent than in composition A. Composition C contained anemulsion polymer in accordance with the present invention and the samewater-soluble solvent as present in composition A.

    ______________________________________                                        Component      A        B         C                                           ______________________________________                                        Rhoplex AC-61  --       --        35.55                                       Acrysol WS-50  74.09    74.09     33.55                                       Titanium Dioxide                                                                             9.42     9.42      9.42                                        Plasticizer    1.92     1.92      1.92                                        Ethylene Glycol                                                                              12.62    --        12.62                                       Propylene Glycol                                                                             --       12.62     --                                          Ammonium Hydroxide                                                                           1.81     1.81      1.81                                        ______________________________________                                    

After preparation of this composition it was found that composition Aimmediately formed a hard, stiff gel and composition B formed a gel butless stiff or rigid than that formed by composition A. Composition C onthe other hand formed a composition workable as a dressing and anevaluation of the viscosity of composition C yielded the following data:

    ______________________________________                                        Temperature      Viscosity (cps)                                              ______________________________________                                         65°      580,000                                                       70°      360,000                                                       85°      180,000                                                      105°       50,000                                                      120°       20,000                                                      ______________________________________                                    

EXAMPLE 8

A test was run to determine the resistance of the dressing compositionto extensive impact by water. The dressing composition C of Example 7was applied to a Portland cement joint surface which was present betweenglazed ceramic tile on a panel. The panel was arranged in a positiondirectly under a shower-type nozzle. The panel was then subjected todirect impact of water from the nozzle for a period of four hours. Thewater flowed at the rate of four gallons per minute on a surface of foursquare feet of panel. At the end of four hours, the grout dressing stillfirmly adhered to the substrate and appeared to suffer no damage.

EXAMPLE 9 The Dirt Resistance of the Tile Joint Dressing

One objective of this example is to determine at what point in timeafter application of the tile joint dressing on a cement grout that dirtdoes not adhere to the dressing surface. A panel was prepared of ceramictiles mounted edge-to-edge and grouted with a cement-based grout. Thetile grout dressing as described in Example 3 was applied to the groutsurface. Dirt from under the roof deck of the research building of TileCouncil of America was obtained. From this dirt sample, a portion whichpasses through an 80 mesh screen was separated and dried in an oven at180° F. The dirt was then rubbed onto the tile and joints between thetile about 2 hours after the tile grout dressing was applied to thegrout surface. An air compressor having 2-5 psi at the valve opening wasthen used to blow off excess dirt adhering to the surface of the tileand joints. This blower was directed at the surface for a period of 15seconds. The joints on which the tile joint dressing was applied did nothold dirt.

EXAMPLE 10 Dressing Composition As A Covering For Large Porous ReactiveSurfaces

The dressing composition as described in other examples for coveringtile grouts was used for covering a cement block. Such a cement block isoften used as a construction material in both the interior and exteriorof buildings. The tile grout dressing as described in Exammple 3 isapplied on one side of a cement block having the dimensions of 151/2inches × 171/2 inches × 81/2 inches. The dressing was allowed to cure onthe cement block for one day. The block was then submerged into a pan ofwater. The untreated side of the block was found to absorb the water inthe pan. The treated side did not absorb any water as the dressingeffectively sealed the underlying porous cement block surface.

It was noted that after 24 hours of soaking, the treated surface wasstill dry and satisfactory.

EXAMPLE 11

This example describes the evaluation of various polymers to determineif they have the property of reactivity to polyvalent cations which isessential in either or both the emulsion polymer and the alkalithickenable polymer component.

1.0 ml of Acrysol WS-50 is diluted in 100 ml of water. The opticaldensity of this liquid is determined and recorded to be in the 400-500mμ range. 1.0 N calcium chloride solution is then added continuously tothe Acrysol liquid at a steady rate of 0.5 ml/min. The point of maximumchange of optical density was determined and found to correspond at theaddition of 1.25 ml of the calcium chloride solution. The experiment wasrepeated and the endpoint of maximum change of optical density wasdetermined as occurring when 1.27 ml of calcium chloride solution wasadded. The closeness in these results indicates the quantitative natureof the chemical reaction. Therefore, Acrysol WS-50 has the desiredproperties of reactivity in the presence of polyvalent cations.

Similar experiments were carried out with other alkali thickenablepolymers and emulsion polymers. Those polymers in emulsion form thatwere stable to calcium chloride did not show a clear-cut endpoint. Anyinstability at high calcium levels was attributable to a physicalphenomenon rather than a chemical reaction. Water soluble thickenerssuch as methyl cellulose did not show any instability at low calciumlevels.

EXAMPLE 12

Composition E of Example 1 was evaluated to determine its rheology basedupon the consistency and viscosity of the composition. The dressingcomposition was placed into a polyethylene tubular insert of a caulkinggun. The insert was then assembled into the caulking gun and thedressing composition was extruded from a 1.9 mm orifice from the gun atvarious pressures. The weight of the material extruded at each pressurewas recorded after 10 seconds. A measurement of the consistency (C) ofthe composition was calculated based upon the following formula:##EQU1## A plot of C versus pressure as illustrated in the table belowshows a rapidly falling value of C with increasing pressure.

Viscosity is measured on the Brookfield viscosimeter with a TE spindle.The speed of rotation is varied and the apparent viscosity is measured.A comparison in the table below in the viscosity measurements andconsistency measurements indicate an interrelationship. Both of thesemeasurements demonstrate the thixotropic character of the dressingcomposition.

    ______________________________________                                        Pressure            Spindle                                                   psi      C          Speed       Viscosity                                     ______________________________________                                        5        625        2.5         260,000                                       10       196        5.0         176,000                                       20        95        10.0        110,000                                       40        25        20.0         75,000                                       60       9.5        50.0         31,000                                                           100.0        6,000                                        ______________________________________                                    

EXAMPLE 13 Methods of Applying the Dressing Composition

A. For this example, a tile assembly was used comprising a plurality ofglazed ceramic tiles arranged in an edge-to-edge, spaced-apartrelationship wherein the spaces between the tiles form joints containingL & M Dry Cure Grout. This tile assembly or panel was four feet by sixfeet in size. A day after the assembly was grouted with the L & M DryCure Grout, these clean and dry cement joints were treated with the tilegrout dressing composition C of Example 7. The dressing composition wasapplied from toothpaste-type tubes, by an extrusion method.

The tube was moved along the joint surface with the open end of the tubeadjacent to the surface and with the tube continually being depressed byhand with approximately the same pressure. No unusual care was taken tobe neat, i.e., some of the dressing smeared onto the surface of theadjacent tile.

The joints on which the dressing composition was applied were shapedusing one's finger. The tile faces were then cleaned by washing thedressing from their surface with a firm, wet, cellulose sponge. The dampsponge was placed flat against the panel and wiped gently over the wholepanel to remove the excess dressing. The dressing stayed on the jointsalthough being easily washed from the tile face surfaces.

The joints were dusted with a damp cloth. The joints were found to bethoroughly dried within 12 hours and yielded a neat and clean panel withdressing only covering the joint surface.

B. A section of a wall of smoke gray tile grouted with L & M Dry CureGrout was the subject for this Example. The wall was old and containedpowdery surface dirt and mildew. The joints were washed with a milddetergent, flushed with clean water and allowed to dry thoroughly. Thedressing composition C of Example 7 was applied over the dry jointsurface using a caulking gun. The joints were completely covered withsome of the composition smearing onto the tile surfaces.

A wet cellulose sponge was wiped against the tile wall, including thejoint surfaces, removing excess dressing from the tile surface. Afterthe dressing had essentially dried, the tile face surfaces were againdusted with a damp cloth. The dressing composition adhered completelyover the joint surface while the tile surfaces were clean.

C. A wall comprising glazed ceramic wall tile grouted with a dry curegrout based on compositions as described in U.S. Pat. No. 2,934,932, wasprepared for treatment with the dressing composition. The joints werecovered with grease and oily-type soap substances. The joints werecleaned by scrubbing with a cleansing powder and a brush, then flushedwith clean water and allowed to dry. The tile grout dressing was thenapplied to the dry grout surface by using a damp sponge and proceedingin a trowelling-like method. After the joints were covered by thedressing, the tile faces were washed removing the excess dressing fromtheir surface. Thereafter, the tile surfaces were dusted with a dampcloth. Upon completion, the wall looked clean and neat with the dressingadhering only in the joint recesses of the wall leaving the tile facesclean.

D. A panel of 27/8 inches × 27/8 inches quarry tile was set with anemulsion-type mastic on gypsum wall board. The tile was grouted with acomposition of two parts "D" sand and one part Portland cement. Thejoints were then dusted with pure gray Portland cement until the jointswere flush with the adjacent tile surfaces. The joints were allowed todry.

The joints were then covered by brushing the dressing composition C ofExample 7 on the joint surfaces. The whole panel surface was then washedwith a wet sponge. It was difficult to remove the dressing compositionwhere it had covered excess cement which had peviously been rubbed intothe tile. Except for this excess cement, the faces of the tile wereeasily cleaned while a layer of the dressing composition stronglyadhered to the joint surface.

E. The following display panels were prepared over a substrate 18 inches× 24 inches of Transitop from Johns Mansville. The tiles on each of thepanels were arranged in a herringbone pattern.

1. American Olean white crystalline glazed tile, Valencia Shape, groutedwith dry set grout.

2. Interpace, 41/4 inches × 41/4 inches square edge tile grouted withdry set grout.

3. Summitville's Summitstones, Sunburst Series, tile grouted with twoparts "D" sand and one part gray Portland cement, with jointssubsequently dusted with gray Portland cement.

4. Wenczel Crystal Green, 41/4 inches × 41/4 inches tile grouted withdry set grout.

Dressing compositions were prepared in accordance with Example 3,including the addition of pigments to appropriately complement the tilesin these panels. Each dressing composition was appied to the respectivepanel by sponging. The panels were each washed with a wet sponge beingwiped across the panel removing excess dressing from the tile faces. Thepanels were then dusted with a damp cloth.

All of the panels yield neat, clean panels with dressing compositionadhering to the joint surfaces and leaving the tile surfaces clean.

What is claimed is:
 1. a dressing composition capable of selectivelyadhering to substrate surfaces and forming on adherable substratesurfaces a non-porous, strain resistant, washable layer when cured, saidcomposition comprisingi. a high molecular weight polymer in the form ofan emulsion which is alkali-thickenable whereby it is capable ofsubstantially increasing the viscosity of the composition as the pH ofthe composition is increased above nertral pH; ii. a high molecularweight polymer in the form of an emulsion which is notalkali-thickenable; iii. an alkaline agent wherein the cation or cationsof said agent are mono-valent, said alkaline agent present in sufficientamounts to cause the alkali-thickenable polymer to increase theviscosity of the composition; and iv. water;wherein both of saidpolymers are room temperature curable and form water resistant filmswhen cured and wherein the dispersion of at least one of said polymersbecomes destabilized in the presence of polyvalent cations whereby itsemulsion phase is broken and the droplets of the polymer no longerremain suspended in the liquid phase and wherein the total weight ofpolymer solids is in the range of 5-60% by weight of the totalcomposition, the volatile components comprising at least 20% by weightof the total composition and the composition having a thixotropicrheology with a viscosity greater than about 50,000 cps at 70° F.
 2. Thecomposition of claim 1 wherein both polymers become destabilized in thepresence of polyvalent cations.
 3. The composition of claim 1 whereinthe non-alkali thickenable polymer in the form of an emulsion isanionically dispersed.
 4. The composition of claim 1 further comprisinga pigment in an amount wherein the weight ratio of the total polymercomponents to the pigment components is 1:1 or greater.
 5. A dressingcomposition capable of selectively adhering to substrate surfaces andforming on adherable substrate surfaces a non-porous, stain resistant,washable layer when cured, said composition comprisingi. a highmolecular weight polymer in the form of an emulsion which is notalkali-thickenable and which emulsion is destabilized in the presence ofpolyvalent cations whereby the droplets of the polymer no longer remainsuspended in the liquid phase, said polymer selected from the groupconsisting of polymers of carboxylic acids, polymers of esters ofcarboxylic acids, and copolymers of a carboxylic acid or ester of acarboxylic acid with one or more monomers from the group consisting ofcarboxylic acids, esters of carboxylic acids, acrylonitriles,acrylamides, aromatic compounds and alkenes, said polymer characterizedas being room-temperature curable and forming a water-resistant filmwhen cured; ii. a high molecular weight polymer which isalkali-thickenable whereby it is capable of substantially increasing theviscosity of the composition as its pH is increased above neutral pH,said polymer in the form of a colloidal dispersion or emulsion ofpolymer particles which dispersion or emulsion is destabilized in thepresence of polyvalent cations, said polymer selected from the groupconsisting of polymers of carboxylic acids, polymers of esters ofcarboxylic acids, and copolymers of a carboxylic acid or ester of acarboxylic acid with one or more monomers from the group consisting ofcarboxylic acids, esters of carboxylic acids, acrylonitriles,acrylamides, aromatic compounds and alkenes, said polymer characterizedas being room-temperature curable and forming a water-resistant filmwhen cured; iii. an alkaline agent wherein the cation or cations of saidagent are mono-valent, said alkaline agent present in sufficient amountsto cause the alkalithickenable polymer to increase the viscosity of thecomposition; and iv. water; wherein the total weight of polymer solidsis in the range of 5-60% by weight of the total composition, and whereinthe composition has a thixotropic rheology and a viscofity which isgreater than about 50,000 cps at 70° F.
 6. The dressing composition ofclaim 5 wherein volatile components of the composition comprise at least20% by weight of the composition and the alkaline agent is present in anamount sufficient to adjust the pH of the composition to greater than 7.7. The composition of claim 5 wherein at least 5% of the polymer solidscomprise the non-alkali thickenable emulsion polymer (i).
 8. Thecomposition of claim 5 wherein the non-alkali thickenable polymer in theform of an emulsion is a polymer of an alpha-olefinic monocarboxylicacid.
 9. The composition of claim 5 wherein the non-alkali thickenablepolymer is a copolymer wherein at least one of the monomers is selectedfrom the group consisting of acrylic acid, and esters of acrylic acid.10. The composition of claim 5 wherein said non-alkali thickenablepolymer is an acrylic emulsion polymer.
 11. The composition of claim 5wherein the alkali thickenable polymer has an acid monomer content offrom 6 to 25% by weight of the polymer.
 12. The composition of claim 5wherein the alkaline agent is monobasic.
 13. The composition of claim 12wherein the monobasic alkaline agent is selected from ammonium andalkali metal hydroxides.
 14. The dressing composition of claim 5 whereinsaid composition further comprises a solvent capable of inhibiting thetime rate of film formation of the composition and present in an amountsufficient to allow adequate time for the composition to be suitablyapplied to a substrate.
 15. The composition of claim 14 wherein thesolvent is water soluble and has a vapor pressure at room temperaturelower than that of water.
 16. The composition of claim 15 wherein thesolvent is a short-chain diol.
 17. The composition of claim 16 whereinthe solvent is ethylene glycol.
 18. The composition of claim 5 furthercomprising a pigment component.
 19. The composition of claim 18 whereinsaid pigment is present in sufficient amount to render the curedcomposition with sufficient opacity to obscure the substrate surface.20. The composition of claim 5 further comprising a coalescing aid forinhibiting the cracking of the composition when cured.
 21. Thecomposition of claim 20 wherein said coalescing aid is selected from thegroup consisting of diacetone alcohol and Butyl Cellosolve.
 22. Thecomposition of claim 5 further comprising a plasticizer.
 23. Thecomposition of claim 5 wherein said composition further comprises amicrobicide.
 24. A tile grout dressing composition capable ofselectively adhering to grout surfaces and forming on adherable groutsurfaces a non-porous, stain resistant, washable layer when cured, saidcomposition comprisingi. a high molecular weight polymer in the form ofan emulsion which is not alkali-thickenable, which emulsion isdestabilized in the presence of polyvalent cations, said polymerselected from the group consisting of polymers of carboxylic acids,polymers of esters of carboxylic acids, and copolymers of a carboxylicacid or ester of a carboxylic acid with one or more monomers from thegroup consisting of the carboxylic acids, esters of carboxylic acids,acrylonitriles, acrylamides, aromatic compounds and alkenes, saidpolymer characterized as being room-temperature curable and forming awater-resistant film when cured; ii. an alkali-thickenable highmolecular weight polymer capable of substantially increasing theviscosity of the composition as its pH is increased above neutral pH,said polymer in the form of a colloidal dispersion or emulsion ofpolymer particles which dispersion or emulsion is destabilized in thepresence of polyvalent cations, said polymer selected from the groupconsisting of polymers of carboxylic acids, polymers of esters ofcarboxylic acids, and copolymers of a carboxylic acid or ester of acarboxylic acid with one or more monomers from the group consisting ofthe carboxylic acids, esters of carboxylic acids, acrylonitriles,acrylamides, aromatic compounds and alkenes, said polymer characterizedas being room temperature curable and forming a water-resistant filmwhen cured; iii. an alkaline agent wherein the cation or cations of saidagent are mono-valent and said alkaline agent is present in sufficientamounts to cause the alkali-thickenable polymer to increase theviscosity of the composition; iv. water; and v. a solvent having a vaporpressure at room temperature lower than that of water and capable ofinhibiting the time rate of film formation of the composition andpresent in an amount sufficient to allow adequate time for thecomposition to be suitably applied to a substrate;wherein the totalweight of polymer solids is in the range of 5-60% by weight of the totalcomposition, at least 5% by weight of the total polymer solids is thepolymer in the form of an emulsion, and the volatile components compriseat least 20% by weight of the composition, and wherein the compositionhas a thixotropic rheology and a viscosity which is greater than about50,000 cps at 70° F.
 25. The composition of claim 24 wherein thenon-alkali thickenable polymer is a copolymer wherein at least one ofthe monomers present is selected from the group consisting of acrylicacid, homologues of acrylic acid, esters of acrylic acid, and esters ofhomologues of acrylic acid.
 26. The composition of claim 24 wherein thealkali thickenable polymer is in the form of a sol of colloidal polymerparticles, said polymer having an acid monomer content of from 6 to 25%by weight of the polymer.
 27. The composition of claim 24 wherein thesolvent is a short-chain diol.
 28. The composition of claim 24 furthercomprising a pigment component present in a sufficient amount to renderthe cured composition with sufficient opacity to obscure a substratesurface on which it is applied, and wherein the weight ratio of totalpolymer solids to pigment component is 1:1 or greater.
 29. Thecomposition of claim 24 further comprising a coalescing aid orplasticizer or both.
 30. The composition of claim 24 wherein saidcomposition further comprises a microbicide.